论文标题
在美国超越SARS-COV-2
Superspreading of SARS-CoV-2 in the USA
论文作者
论文摘要
众所周知，许多流行病，包括2002 - 2004年的SARS-COV-1流行病，表现出超级广泛，其中一小部分受感染的个体造成了大多数新感染。超级广泛的存在意味着不同个体中感染性的脂肪分布（每天引起的新次生感染）。在这里，我们提出了一种简单的方法，可以通过检查不同亚群中新病例的早期增长率的差异来估计感染性的变化。我们使用这种方法来估计在美国大流行的早期，SARS-COV-2传播的传染性$β$的平均值和差异。我们发现$σ_β/μ_β\ gtrsim 3.2 $，其中$μ_β$是平均传染性，其标准偏差为$σ_β$，这意味着普遍存在的超级传播。这一结果使我们能够估计，在美国大流行的早期阶段，超过81％的新病例是大多数传染性人群中前10％的结果。
A number of epidemics, including the SARS-CoV-1 epidemic of 2002-2004, have been known to exhibit superspreading, in which a small fraction of infected individuals is responsible for the majority of new infections. The existence of superspreading implies a fat-tailed distribution of infectiousness (new secondary infections caused per day) among different individuals. Here, we present a simple method to estimate the variation in infectiousness by examining the variation in early-time growth rates of new cases among different subpopulations. We use this method to estimate the mean and variance in the infectiousness, $β$, for SARS-CoV-2 transmission during the early stages of the pandemic within the United States. We find that $σ_β/μ_β\gtrsim 3.2$, where $μ_β$ is the mean infectiousness and $σ_β$ its standard deviation, which implies pervasive superspreading. This result allows us to estimate that in the early stages of the pandemic in the USA, over 81% of new cases were a result of the top 10% of most infectious individuals.
